Bioaccumulation of mycotoxins by shellfish: Contamination of mussels by metabolites of a Trichoderma koningii strain isolated in the marine environment

To determine whether toxic metabolites produced by fungi could cause shellf ish toxicities, mussels were contaminated in laboratory conditions by steri le filtrates of a liquid culture of a strain of the fungus Trichoderma koni ngii previously isolated from a shellfish, the cockle (Cerastoderma edule). Mussels were kept in aerated natural seawater and fed with a culture of th e microalga Isochrysis galbana, to which a filtrate of liquid fungal cultur e was added. Mussels were exposed to contamination for 7 days at 16 or 20 d egrees C and extractions were then performed and their activity tested on b lowfly larvae. The same toxicity was found in the fungal filtrate and the s hellfish, indicating bioaccumulation. The digestive gland was the most toxi c part of the mussel, confirming contamination by filtration. Treated musse ls produced a mucus which appeared to be a means of eliminating toxic metab olites. (C) 1998 Elsevier Science Ltd. All rights reserved.